package com.problem.leetcode;

public class Problem141 {



    public boolean hasCycle(ListNode head) {
        if (head == null) {
            return false;
        }

        ListNode slow = head;
        ListNode fast = head.next;

        while (fast != null) {
            if (slow == fast) {
                return true;
            }
            slow = slow.next;
            fast = fast.next;

            if (fast != null) {
                fast = fast.next;
            }

        }
        return false;
    }


}
